Purge download boxes when a new release is added
Purge download boxes when a new release is added

Closes #584

manhhomienbienthuy/pythondotorg,manhhomienbienthuy/pythondotorg,python/pythondotorg,Mariatta/pythondotorg,proevo/pythondotorg,Mariatta/pythondotorg,proevo/pythondotorg,python/pythondotorg,proevo/pythondotorg,Mariatta/pythondotorg,python/pythondotorg,manhhomienbienthuy/pythondotorg,Mariatta/pythondotorg,manhhomienbienthuy/pythondotorg,proevo/pythondotorg,python/pythondotorg